JP2014509489A - Cell selection method and apparatus in heterogeneous network - Google Patents

Abstract

  A cell selection method and apparatus in a heterogeneous network. Estimating the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using the method and parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal Mapping the estimated signal-to-noise ratio to throughput to determine a first throughput when scheduled by a macro base station and a second throughput when scheduled by a low power base station; and the first throughput And adjusting the cell selection deviation amount based on the second throughput, and the terminal performing cell selection based on the adjusted cell selection deviation amount. According to the embodiment of the present invention, the cell selection mechanism can be optimized, and the resource utilization rate and throughput of the system can be further improved.

Description

  The present invention relates generally to the field of wireless communication technology, and more particularly to a cell selection method and apparatus in a heterogeneous network.

  In order to improve the user coverage rate in LTE-A (long term evaluation advanced) system and improve the system throughput and user data transmission rate, there are some differences from the conventional cellular network These network nodes are referred to as heterogeneous network nodes, and correspondingly, a network having not only a conventional cellular network network node but also a heterogeneous network node is: It is called a heterogeneous network.

  Among them, the heterogeneous network node may normally include HeNB (Home eNodeB, home base station), Pico-cell (pico cell), and the like. Speaking of network nodes in conventional cellular networks, these heterogeneous nodes have features such as low transmission power (power), coverage for specific areas or users, and flexible network configuration schemes, etc. If it is reasonable, the user coverage rate in the LTE-A system can be greatly improved. For convenience of explanation, a network node of a conventional cellular network is referred to as a macro base station, and a heterogeneous node is referred to as a low power base station.

  In actual application, the terminal performs cell selection based on the level of RSRP (Reference Signal Received Power) received from each base station, and the cell of the base station with the highest received RSRP. Belonging to. The RSRP received by the terminal relates not only to the distance (distance) to the base station but also to the transmission power of the base station. However, as described above, in the heterogeneous network, since the transmission power of the low power base station is relatively low, the following situation may exist, that is, the 某 terminal is located at the boundary of the 某 macro cell. When the distance to the macro base station is relatively long, and at the same time, a low power base station is also arranged near the terminal, and the area covered by the low power base station is a Pico cell, the terminal measures The RSRP of the macro base station may still be higher than the RSRP of the low power base station, so that the terminal finally belongs to the macro cell at the time of cell selection. However, if the terminal actually belongs to the Pico cell, there is a possibility of obtaining a higher data transmission rate. In terms of the entire network, the resource utilization rate and throughput of the system can be improved.

  In order to make more users belong to the Pico cell based on the above-mentioned idea, the conventional technology introduces “RSRP + bias” biased to the Pico cell when performing cell selection based on RSRP. Among them, bias corresponds to a deviation amount (offset), and when the terminal performs cell selection, after measuring the RSRP of the macro base station and the low power base station, first, the bias is added to the RSRP of the low power base station. And then compare with the RSRP of the macro base station, and finally select the target cell to which it belongs. As is apparent, this type of scheme can allow more users to belong to the Pico cell, which is advantageous for improving system resource utilization and throughput.

  However, the deviation “bias” in the prior art is a cell level parameter, that is, all terminals in the same cell perform cell selection using the same “bias”. However, since this unified “bias” is not suitable for all terminals, the improvement of the resource utilization rate and throughput of the system is limited.

  In view of the above, embodiments of the present invention provide a cell selection method and apparatus in a heterogeneous network that can optimize the cell selection mechanism and further improve the resource utilization and throughput of the system.

  According to an aspect of an embodiment of the present invention, a cell selection method in a heterogeneous network is provided. The method uses a parameter related to signal reception quality of a macro base station and a low power base station measured by a terminal, and a signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively. Mapping the estimated signal-to-noise ratio to the throughput to obtain a first throughput when scheduled by the macro base station and a second throughput when scheduled by the low power base station; and , Adjusting the cell selection deviation amount based on the first throughput and the second throughput, whereby the terminal performs cell selection based on the adjusted cell selection deviation amount .

  According to another aspect of an embodiment of the present invention, a cell selection device in a heterogeneous network is provided. The apparatus calculates a signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters regarding the signal reception quality of the macro base station and the low power base station measured by the terminal. A signal-to-noise ratio estimation unit configured to estimate; the estimated signal-to-noise ratio is mapped to throughput and is scheduled by a macro base station, and is scheduled by a low power base station A throughput mapping unit configured to obtain a second throughput of time; and adjusting the cell selection deviation based on the first throughput and the second throughput, thereby adjusting the terminal A deviation amount configured to perform cell selection based on the subsequent cell selection deviation amount Including an integer unit.

  According to another aspect of an embodiment of the present invention, a terminal is provided. The terminal includes a measurement unit configured to measure parameters related to signal reception quality of a macro base station and a low power base station; and a cell selection device in the heterogeneous network described above.

  According to another aspect of an embodiment of the present invention, a base station in a heterogeneous network is provided. The base station includes a cell selection device in the heterogeneous network described above.

  According to another aspect of the present invention, a recording medium is provided. The recording medium includes a machine-readable program code. When the program code is executed in an information processing facility, the program code causes the information processing facility to perform the cell selection method in the heterogeneous network according to the present invention. Let it run.

  According to another aspect of the present invention, a program product is provided. The program product includes a machine-executable command, and when the information processing facility executes the command, the command causes the information processing facility to execute the cell selection method in the heterogeneous network according to the present invention. .

  According to the above-described method in the embodiment of the present invention, when performing cell selection, base stations with different users (terminals) using parameters related to signal reception quality in the macro base station and the low power base station obtained by the terminal. Estimate the performance gain when scheduled by the station, and then select an individual (dedicated) cell selection deviation for each terminal, thus the terminal will have its own dedicated cell selection deviation Cell selection can be performed based on the above. Therefore, the cell selection mechanism can be optimized, and the resource utilization rate and throughput of the system can be further improved.

  In the following part of the specification, other aspects of embodiments of the invention will be described, of which the detailed description is only for the purpose of fully disclosing preferred embodiments of the invention, It is not intended to limit the invention.

The above and other objects and advantages of embodiments of the present invention will be further described below with reference to specific embodiments and the accompanying drawings. In the drawings, the same or corresponding technical features or parts are represented by the same or corresponding reference numerals.
3 is a flowchart of a method provided by an embodiment of the present invention. 1 is a diagram showing a first device provided by an embodiment of the present invention. FIG. 3 shows a second device provided by an embodiment of the present invention. FIG. 6 shows a third device provided by an embodiment of the present invention. It is a figure which shows the 4th apparatus provided by the Example of this invention. It is a figure which shows the 5th apparatus provided by the Example of this invention. It is a figure which shows the 6th apparatus provided by the Example of this invention. FIG. 3 is a diagram illustrating a terminal provided by an embodiment of the present invention. It is a block diagram of an exemplary configuration of a personal computer as information processing equipment employed in an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  Referring to FIG. 1, a cell selection method in a heterogeneous network provided by an embodiment of the present invention includes the following steps.

  S101: Estimating the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using the parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal. .

  In actual application, the parameters related to the signal reception quality may include the reference signal reception power and the reference signal reception quality, that is, the two parameters relate to the signal reception quality. Of course, other parameters may be used as parameters related to signal reception quality, and are not limited here. However, for convenience of explanation, all of the embodiments of the present invention introduce the reference signal reception power and the reference signal reception quality as parameters relating to the signal reception quality.

  In the LTE-A network, the reference signal reception power may be expressed as RSRP, and the reference signal reception quality may be expressed as RSRQ. For convenience of explanation, all of the embodiments of the present invention introduce LTE-A networks as examples. However, it should be understood by those skilled in the art that the embodiments of the present invention are not limited to LTE-A networks. It can be applied to other networks.

  As can be seen, in the embodiment of the present invention, in addition to measuring the RSRP of the base station and the low power base station, the terminal needs to measure the RSRQ of the base station, and the two parameters are set. , Parameters related to signal reception quality.

  In the LTE-A network, there are usually a large number of macro base stations and low power base stations, and in the embodiment of the present invention, what kind of base station RSRP and RSRQ need to be measured by the terminal, There are several specific implementation methods. For example, in one scheme, the base station of the cell to which the terminal currently belongs constitutes a list of adjacent cells for the terminal, and thus the terminal can list the cell to which it currently belongs and the list of adjacent cells. What is necessary is just to measure the RSRP and RSRQ values of the base station of each cell. Thus, the base station as a measurement target may include a macro base station and may include a low power base station.

  Of course, in some cases, the base station may not be able to construct a list of neighboring cells for the terminal. In such a case, the method according to embodiments of the present invention can still be realized. For example, whether it is a macro base station or a low power base station, its transmission power is all limited, that is, the signal coverage range of the base station is limited. Therefore, for one terminal, the number of macro base stations and low power base stations that can receive the signal is also limited. Usually, when the distance from the terminal to the base station approaches a certain level (predetermined value), the terminal can receive a signal from the base station. Therefore, in the embodiment of the present invention, when the terminal measures the PSRP and RSRQ of the base station, the terminal may perform as follows: the terminal is a base station (the base station of the cell to which it currently belongs and its neighbor If the signal can be received from the cell base station), the RSRP and RSRQ of the base station can be measured. Similarly, the base station as a measurement target may include a macro base station. And may include low power base stations. Of course, if all the base stations that can be measured by the terminal are the same type of base station, for example, if all base stations are macro base stations or all base stations are low power base stations, cell selection can be performed using a method in the prior art The detailed description is omitted here.

  In an actual application, since the cell selection is usually performed only when the position of the に terminal is at the boundary of the 某 cell, in the embodiment of the present invention, the terminal uses the RSRP and the macro base station and the low power base station. Before measuring RSRQ, it can first be determined whether the terminal is located at the boundary of the cell to which it currently belongs. If the determination result is “Yes”, then the measurement process is performed, otherwise the terminal is at the center position of the cell, and in this case, relatively high performance is scheduled when scheduled by the base station of the cell. Therefore, it is not necessary to switch cells, that is, the terminal does not need to perform measurement processing.

  After measuring the RSRP and RSRQ of the base station, the terminal estimates the signal-to-noise ratio of the received signal of the terminal when the terminal is scheduled by the base station based on the measured RSRP and RSRQ values Can do. The same processing is performed for other base stations as measurement targets. In this way, the terminal can estimate the signal-to-noise of the received signal of the terminal when being scheduled by each base station as the measurement target.

  Among them, a specific method for estimating a signal-to-noise ratio when a terminal is scheduled by the base station based on the measured RSRP and RSRQ of the base station is a method known in the art by a person skilled in the art. For example, SINR = S / (I + N), of which RSRP = S, RSRQ = S / (S + I + N), and therefore SINR = RSRP / ( RSRP / RSRQ-RSRP).

  S102: The estimated signal-to-noise ratio is made into a throughput by mapping, and a first throughput when scheduled by the macro base station and a second throughput when scheduled by the low power base station are obtained.

  Since the throughput of terminal reception data is a kind of quantified expression for performance, it represents the spectrum efficiency when scheduling a terminal using a certain resource. Therefore, after estimating the signal-to-noise ratio of the received signal of the terminal when scheduled by the base station, the signal-to-noise ratio can be further mapped to the throughput (ie, converted into the throughput). Among them, a specific mapping method from the signal-to-noise ratio to the throughput can be similarly performed by a person skilled in the art by adopting a method in the prior art, and thus detailed description thereof is omitted here.

  S103: The cell selection deviation is adjusted based on the first throughput and the second throughput acquired in S102, whereby the terminal performs cell selection based on the adjusted cell selection deviation. Do.

  Since the size (size) of the throughput can represent the level of performance gain, various specific methods are used when adjusting the cell selection deviation based on the first and second throughputs. May be. For example, in one method, the cell selection deviation amount can be adjusted by directly comparing the magnitudes of the first throughput and the second throughput.

Thus, when the first throughput is larger than the second throughput, it is proved that a larger performance gain can be obtained when the terminal is scheduled by the macro base station. Can be reduced. This means that the degree to which the terminal is biased toward cell selection of the low power base station may not be high. For example, the macro base station's RSRP measured by the terminal is P ₁ and PSRQ is Q ₁ , and the low power base station's RSRP is P ₂ and PSRQ is Q ₂ , and the throughput obtained for the macro base station Is T ₁ and the throughput obtained for the low power base station is T ₂ , of which P ₁ > P ₂ and T ₁ > T ₂ . When the initial value of the cell selection deviation amount is Qoffset and P ₁ <P ₂ + Qoffset, when performing cell selection directly based on the cell selection deviation amount, the terminal Access to the cell can be selected. However, when the terminal is scheduled by the low power base station, the performance gain is actually lower than the performance gain when scheduled by the macro base station, so the access to the cell of the low power base station is selected. After that, the performance gain will decrease. However, in the embodiment of the present invention, since T ₁ and T ₂ are estimated in advance and T ₁ > T ₂ , first, the cell selection deviation amount can be reduced, for example, after adjustment The cell selection deviation amount is Qoffset-Δ_Qoffset, and cell selection is performed using the adjusted cell selection deviation amount, that is, P ₁ is compared with (P ₂ + Qoffset-Δ_Qoffset) To do. As is apparent, in this case, since P ₁ may be larger than (P ₂ + Qoffset−Δ_Qoffset), the terminal may select the cell of the macro base station. Of course, if P ₁ is still smaller than (P ₂ + Qoffset−Δ_Qoffset), the terminal can select the cell of the low power base station, at which time the signal received by the terminal from the low power base station It means that the strength of is surely very strong. Therefore, it is possible to select access to the cell of the low power base station, thereby preventing the system performance from being deteriorated too much.

Conversely, if the first throughput is less than or equal to the second throughput, it is proved that a higher performance gain can be obtained when the terminal is scheduled by the low power base station, so that the cell selection deviation amount is appropriately set. Can be increased. This means that the degree to which the terminal is biased toward the cell selection of the low power base station may be higher. For example, the macro base station's RSRP measured by the terminal is P ₁ and PSRQ is Q ₁ , and the low power base station's RSRP is P ₂ and PSRQ is Q ₂ , and the throughput obtained for the macro base station Is T ₁ and the throughput obtained for the low power base station is T ₂ , of which P ₁ > P ₂ and T ₁ <T ₂ . If the initial value of the cell selection deviation amount is Qoffset and P ₁ > P ₂ + Qoffset, when performing cell selection directly based on the cell selection deviation amount, the terminal Access to the cell can be selected. However, since the performance gain when the terminal is scheduled by the macro base station is actually lower than the performance gain when scheduled by the low power base station, the access to the cell of the macro base station is selected. After that, the performance gain will drop. However, in the embodiment of the present invention, since T ₁ and T ₂ are estimated in advance and T ₁ <T ₂ , first, the cell selection deviation amount can be increased. The subsequent cell selection deviation amount is Qoffset + Δ_Qoffset, and then cell selection is performed using the adjusted cell selection deviation amount, that is, the magnitude of P ₁ and (P ₂ + Qoffset + Δ_Qoffset) Compare. As is evident, in this case, because P ₁ is less likely than (P2 + Qoffset + Δ_Qoffset), the terminal is likely to select a cell in the low power base station. Of course, if P ₁ is still larger than (P ₂ + Qoffset + Δ_Qoffset), the terminal can select the cell of the macro base station, and at this time, the strength of the signal received by the terminal from the macro base station is It means that it is definitely very strong, so that the access of the macro base station to the cell can be selected.

  Of course, in an actual application, as an example of a kind of option, the cell selection deviation amount may be adjusted by another method. For example, after obtaining the first throughput and the second throughput, first, the difference between the two is obtained, and the difference is compared with some predetermined threshold, and then, based on the final comparison result, It is also possible to determine which cell the terminal belongs to more appropriately, and then adjust the cell selection deviation amount.

  It should be noted that the threshold value and the cell selection deviation amount adjustment amount Δ_Qoffset, etc. mentioned in the embodiments of the present invention may be set in advance by experience.

  In the embodiment of the present invention, description will be made using the first throughput and the second throughput. This is because the macro base station has only one base station as an actual measurement target and only one low power. Does not mean having a base station. As described above, there are a plurality of base stations as actual measurement targets. However, in the embodiment of the present invention, the cell selection is mainly different from a cell type (for example, a macro base station and a low power base station). It is important to emphasize the throughput obtained for two different cell types. However, it should be understood by those skilled in the art that when the number of base stations as actual measurement objects is plural, the cell selection deviation amount can still be adjusted using the above-described method. Therefore, detailed description is omitted here. For example, if the throughput of a plurality of macro base stations and the throughput of a plurality of low power base stations are acquired simultaneously, one maximum is selected from the throughputs of the plurality of macro base stations, and one throughput is selected from the throughput of the low power base stations. The largest one can also be selected and an adjustment can be made to the cell selection deviation based on the two maximum values. Of course, other schemes may be adopted and not described here.

  Further, in the method according to the embodiment of the present invention, after the terminal measures the RSRP and RSRQ of the base station, the subsequent processes such as estimation, mapping and adjustment may be completed independently by the terminal, May be completed by a base station of a cell belonging to. For example, if the terminal is currently connected, i.e., is transmitting data, after measuring the RSRP and RSRQ of the base station, transmit them to the base station of the cell that currently belongs, and the base station Steps S101 to S103 are executed. In this case, if the base station determines that it is necessary to switch the terminal to another cell after obtaining the adjustment value of the cell selection deviation amount, it directly issues a switching command (command) to switch the cell. At the same time, the adjusted cell selection shift amount can be transmitted to the terminal. In this way, when the terminal performs subsequent cell selection, the terminal can perform selection using the adjusted cell selection shift amount. Of course, in order to save resources, a cell-level cell selection shift amount can be provided to each terminal in advance. In this way, the base station can transmit only the adjustment value of the cell selection deviation amount to the terminal, and can cause the terminal itself to calculate the adjusted cell selection deviation amount.

  The terminal may perform steps S101 to S103 independently after measuring the RSRP and RSRQ of the base station when in the non-connected state, and after obtaining the adjustment value of the cell selection deviation amount, If it is necessary to access another cell, an access request may be transmitted to the base station of the cell to complete the access. Of these, when the terminal completes steps S101 to S103 independently, it is possible even if the terminal is currently connected. Of these, if the terminal is currently in a disconnected state, the measurement and steps S101 to S103 may be performed after receiving the higher layer command. If the terminal is currently connected, a measurement event is configured for the terminal by the cell that currently belongs, and after the terminal measures the RSRP and RSRQ of the base station, it adjusts itself for the cell selection deviation amount. And then cell selection. Of these, whether it is a higher layer command or the configuration of this cell, everything can be done when the terminal is detected to be at the cell boundary.

  As can be seen from the above, in the embodiment of the present invention, when cell selection is performed, parameters related to signal reception quality of the terminal are taken into account, for example, signal strength (RSRP can represent signal strength). As well as taking into account the interference received by the terminal by a parameter called reference signal reception quality (ie, RSRQ), thereby estimating the performance gain when users are scheduled by different base stations, Thereafter, an individual (dedicated) cell selection shift amount is selected for each terminal. In this way, since a terminal can perform cell selection based on its own dedicated cell selection shift amount, it is possible to optimize the cell selection mechanism and further improve the resource utilization rate and throughput of the system. it can.

  In an actual application, each base station can perform scheduling using all resources without considering interference between adjacent cells. Here, the resource may refer to a resource on the time domain or a resource on the frequency domain. In the embodiment of the present invention, description will be made only in terms of the time domain, but similar processing may be performed for the frequency domain.

  Resources in the time domain usually exist in the form of subframes. If each base station can perform scheduling for all terminals using all resources, this means that the base station can perform scheduling for terminals on all subframes. In this case, when the terminal measures the RSRP and RSRQ of the base station, whether it is a macro base station or a low power base station, all can measure its RSRP and RSRQ on all subframes. Thereafter, the signal-to-noise ratio is estimated using the measured RSRP and RSRQ, mapped to the throughput, and finally, the cell selection deviation amount may be adjusted.

  In order to facilitate understanding, a case where each base station performs scheduling for a terminal on all subframes will be described in more detail with specific examples.

  Example 1: In Example 1, it is assumed that the terminal is currently in a connected state, and the base station of the cell belonging to the present performs steps S101 to S103.

  Specifically, if a cell that currently belongs to a terminal (for convenience of explanation, a cell that currently belongs is referred to as a main cell) is a macro cell of the base station, this cell and its neighboring cells Measure the RSRP and RSRQ of the corresponding base station in the cell (including the low power base station cell Pico cell) respectively, and the corresponding base station in the Macro cell (for convenience of explanation, Macro The corresponding base station in the cell is called MeNB, and the corresponding base station in the Pico cell is called PeNB. (In this example, there is only one macro base station and only one power base station, but embodiments of the present invention are not limited to this.) Subsequently, the MeNB performs the following process.

  (1) The MeNB calculates as follows based on RSRP and RSRQ from the terminal.

  The signal-to-noise ratio (SINR) when the terminal is scheduled by the MeNB is calculated and mapped to the throughput T_m. The SINR when the terminal is scheduled by the PeNB is calculated and mapped to the throughput T_p.

  (2) Based on performing an estimation on the performance when the terminal is scheduled by different base stations, the MeNB determines whether the terminal belongs to the Macro cell or the Pico cell, and then the cell Adjust the value of the selected deviation amount Qoffset. The determination method may be as follows.

If T_m <T_p, it can be determined that the terminal belongs to the Pico cell more appropriately, and the Qoffset value can be adjusted upward (larger), and vice versa. Or
T_p-T_m is compared with some thresholds to determine what cell the terminal belongs to appropriately, and this difference is mapped to a Qoffset value.

  Of course, other factors may be considered in actual applications. For example, the load of each cell can be considered. In this case, the determination method may be as follows.

If α × T_m <β × T_p, it can be determined that the terminal belongs to the Pico cell more appropriately, and the Qoffset value can be adjusted upward (larger), and vice versa. Or
α × T_p−β × T_m is compared with several thresholds to determine which cell the terminal belongs to appropriately, and this difference is mapped to a Qoffset value.

  Of these, α and β are parameters for adjusting the estimated value of the throughput based on the situation such as the load of each cell, and the specific values may be determined by the actual load situation. .

  (3) Cell selection is performed based on the calculated specific Qoffset value of each terminal, and a cell-specific Qoffset adjustment amount is transmitted to each terminal by signaling such as paging.

  If the terminal is currently connected and the base station of the cell that currently belongs performs steps S101 to S103, if the base station of the cell that currently belongs to the terminal is a low power base station, specific processing Is similar to the above, and the MeNB may be changed to a low power base station (for example, PeNB), and detailed description thereof is omitted here.

  Example 2: In Example 2, it is assumed that the terminal is currently in a disconnected state and the terminal independently performs steps S101 to S103.

  Specifically, if this cell is a macro cell of a certain macro base station, the terminal may complete the following processing.

  (1) Under the measurement event configured by the upper layer, measure the RSRP and RSRQ of the corresponding base station in this cell and adjacent cells (including the low-power base station cell Pico cell), respectively. To do.

  (2) The terminal calculates as follows based on the measured RSRP and RSRQ, respectively.

  The SINR when the terminal is scheduled by the MeNB is calculated and mapped to the throughput T_m. The SINR when the terminal is scheduled by the PeNB is calculated and mapped to the throughput T_p.

  (3) Based on making an estimate on the performance when the terminal is scheduled by different base stations, the terminal determines whether the terminal belongs to the Macro cell or the Pico cell, and then The value of the cell selection deviation amount Qoffset is adjusted. The determination method may be as described in Example 1.

  (4) Cell selection is performed based on the calculated specific Qoffset value of the terminal.

  If the terminal is currently in a disconnected state and the terminal independently executes steps S101 to S103, if the base station of the cell that currently belongs to the terminal is a low power base station, the specific processing is as described above. The detailed description is omitted here.

  The case where all base stations perform scheduling for terminals on all subframes has been introduced in detail. However, in an actual application, in order to reduce interference with other cells, there is a possibility that some subframes may be configured as an almost blank subframe (ABS). In ABS, the macro base station transmits only a common reference signal and the very few control channels required. If it is necessary for the macro base station to perform scheduling for the terminal, it must be performed only by non-ABS. In the case of a low power base station, since it has a feature of low transmission power, interference with other cells is relatively small. Therefore, the low power base station can perform scheduling for the terminal on all the subframes.

  When ABS as described above is present, the terminal measures the RSRP and RSRQ of the macro base station and the low power base station based on the ABS configuration of the macro base station, and estimates the signal-to-noise ratio. The terminal is scheduled by the macro base station and the low power base station using the macro base station RSRP and RSRQ measured based on the ABS configuration of the macro base station and the RSRP and RSRQ of the low power base station, respectively. The signal-to-noise ratio at the time can be estimated.

  When an ABS is configured in a macro base station, when the cell type to which the terminal currently belongs is different, for the macro base station and the low power base station, the terminal shall measure its RSRP and RSRQ on all subframes. Can do. Of course, in the embodiment of the present invention, the method of specifically measuring the RSRP and RSRQ of different types of base stations differs depending on the cell type currently belonging to the terminal.

  Specifically, if the base station of the cell that currently belongs to the terminal is a macro base station, for the macro base station, the terminal measures the RSRP and RSRQ of the macro base station on the subframe of the non-ABS corresponding position. be able to. For the low power base station, the RSRP and RSRQ of the low power base station can be measured on the subframe of the ABS corresponding position. Thus, when adjusting the cell selection deviation amount based on the first throughput and the second throughput, first, the first throughput is multiplied by the ratio of the number of non-ABSs to the number of all subframes. A first product can be obtained, and a second product can be obtained by multiplying the second throughput by the ratio of the number of ABS to the number of all subframes. Thereafter, the cell selection deviation amount is adjusted based on the first product and the second product obtained by the calculation. The specific adjustment method may be similar to Example 1 and Example 2.

  If the base station of the cell currently belonging to the terminal is a low power base station, for the macro base station, the terminal similarly measures the RSRP and RSRQ of the macro base station on the subframe at the corresponding position of the non-ABS. For the low power base station, the RSRP and RSRQ of the low power base station can be measured on subframes at corresponding positions of ABS and non-ABS, respectively. Thus, when estimating the signal-to-noise ratio, the first signal-to-noise ratio when the terminal is scheduled by the macro base station, the first signal-to-noise ratio when the terminal is scheduled on the ABS by the low power base station A two signal to noise ratio and a third signal to noise ratio when the terminal is scheduled on non-ABS by a low power base station can be estimated. When mapping the estimated signal-to-noise ratio to throughput, the first signal-to-noise ratio is mapped to the first throughput, the second signal-to-noise ratio is mapped to the second throughput, and the third signal-to-noise ratio May be mapped to the third throughput. When adjusting the amount of cell selection deviation based on the first throughput and the second throughput, first multiply the first throughput by the ratio of the number of non-ABSs to the number of all subframes to obtain the third product. Multiply the second throughput by the ratio of the number of ABS subframes to the total number of subframes to get the fourth product, and the third throughput by the number of non-ABS subframes Can be multiplied by the ratio of the total number of subframes to obtain a fifth product. Thereafter, the cell selection shift amount is adjusted based on the third product, the fourth product, and the fifth product obtained by the calculation. The specific adjustment method may be similar to Example 1 and Example 2.

  Among them, for a low power base station, when the base station of the cell belonging to the current terminal is a macro base station, the RSRP and RSRQ are measured only on the subframe at the ABS corresponding position, and the cell belonging to the current terminal The reason why the RSRP and RSRQ are measured on subframes corresponding to ABS and non-ABS respectively when the base station of the base station is a low power base station is as follows. This means that the terminal is very likely to be located at the cell boundary of the low power base station at present, and therefore, even if the terminal is switched to the cell of the low power base station, It is better for the base station to schedule the terminal on the ABS subframe, otherwise there is a possibility that the received macro base station interference will be greater, so the ABS The RSRP and RSRQ of the low power base station are measured only on the corresponding subframe, that is, when the macro base station does not perform scheduling for the terminal.

However, if the base station of the cell that currently belongs to the terminal is a low power base station, the terminal may be located at the center of the cell of the low power base station and may be located at the cell boundary of the low power base station Therefore, the RSRP and RSRQ on the subframe of the ABS corresponding position of the low power base station and the non-ABS corresponding position are respectively measured, and thus, on the subframe of the ABS corresponding position for the low power base station. Can estimate the signal-to-noise ratio of the received signal at the time of scheduling to the terminal and map it to the throughput T ₁ , and also to the terminal on the subframe of the non-ABS corresponding position estimating a signal-to-noise ratio of the received signal of the terminal at the time when performing scheduling Te, and can be mapped to throughput T _2. In this way, the throughputs T ₁ and T ₂ can be simultaneously compared with the throughput T ₃ calculated for the macro base station, and the cell selection deviation amount can be adjusted based on the comparison result. . In this case, there may be a plurality of specific determination methods. For example, if T ₃ > T ₁ and T ₃ > T ₂ , the bias of the terminal may be adjusted downward (smaller), and T3 may be T1 And the bias of the terminal may be adjusted upward (larger) if it is smaller than any one of T2 and T2. Of course, other determination methods may be used, and an exhaustive list is omitted here.

  In the case of configuring an ABS, the configuration of the ABS is usually the same for all macro base stations in the system, that is, on a certain subframe, all macro base stations have a common reference signal and Transmit the very few control channels required. Therefore, the ABS configuration of the macro base station described in the embodiments of the present invention may refer to the ABS configuration of all the macro base stations, that is, all the macro base stations are based on the same ABS configuration. The RSRP and RSRQ may be measured. Of course, in special cases, different ABS configurations may be adopted between the macro base stations. In such a case, RSRP and RSRQ may be measured based on the respective ABS configurations.

  Similarly, in order to make it easier to understand, the case where an ABS is configured in a macro base station will be described in more detail with a specific example.

  Example 3: In this example, the terminal is currently in a connected state, the base station of the cell belonging to the current performs steps S101 to S103, and the base station of the cell currently belonging to the terminal is a macro base station And

  Specifically, if the cell that currently belongs to the terminal is the cell Macro cell of the 某 macro base station, the cell in this cell and an adjacent cell (including the cell Pico cell of the 某 low power base station), respectively. The RSRP and RSRQ of the corresponding base station are measured and reported to the macro cell base station MeNB. Among them, for the macro base station, the RSRP and RSRQ are measured on the subframe of the non-ABS corresponding position, and for the low power base station, the RSRP and RSRQ are measured on the subframe of the ABS corresponding position. Subsequently, the MeNB performs the following process.

  (1) The MeNB calculates as follows based on RSRP and RSRQ from the terminal.

  The signal to noise ratio (SINR) when the terminal is scheduled by the MeNB is calculated and mapped to the throughput T_m, and the SINR when the terminal is scheduled by the PeNB is calculated and mapped to the throughput T_p.

  (2) Based on estimating the performance when the terminal belongs to different base stations, the MeNB further determines whether the terminal belongs to the Macro cell or the Pico cell, and then the cell selection shift. Adjust the value of the quantity Qoffset. The determination method may be as follows.

If T_m × (1-muting_ratio) <T_p × muting_ratio, it may be determined that the terminal belongs to the Pico cell more appropriately, and the Qoffset value may be adjusted upward (larger), and vice versa. . Or
T_p × muting_ratio−T_m × (1−muting_ratio) is compared with some thresholds, it is determined what cell the terminal appropriately belongs to, and the difference is mapped to a Qoffset value.

  Of these, muting_ratio is the ratio of the number of ABSs to the number of all subframes, and (1-muting_ratio) accordingly represents the ratio of the number of non-ABSs to the number of all subframes.

  Similar to Example 1, in practical applications other factors can be considered. For example, you may consider the load of each cell. In this case, the determination method may be as follows.

If α × T_m × (1-muting_ratio) <β × T_p × muting_ratio, it may be determined that the terminal belongs to the Pico cell, and the Qoffset value may be adjusted upward (larger). The same is true. Or
α × T_p × muting_ratio−β × T_m × (1-muting_ratio) is compared with several thresholds to determine which cell the terminal belongs to appropriately, and this difference is mapped to the Qoffset value To do.

  Of these, α and β are parameters for adjusting the estimated throughput based on the load of each cell, and the specific values are determined based on the actual cell load. Also good.

  (3) Cell selection is performed based on the calculated specific Qoffset value of each terminal, and the cell-specific Qoffset adjustment amount is transmitted to each terminal by signaling such as paging. Make a selection.

  Example 4: In this example, it is assumed that the terminal is currently in a connected state, and the base station of the cell that currently belongs to the terminal performs steps S101 to S103. The difference from Example 3 is that the base station of the cell that currently belongs to the terminal is a low power base station.

  Specifically, assuming that the cell currently belonging to the terminal is a cell Pico cell of a low power base station, the corresponding cell in the main cell and the adjacent cells (including the cell Macro cell of the macro base station), respectively. The base station RSRP and RSRQ are measured and reported to the Pico cell base station PeNB. Among them, the macro base station measures its RSRP and RSRQ on the subframes corresponding to the non-ABS, and the low-power base station respectively measures the RSRP and RSRP on the subframes corresponding to the ABS and non-ABS. Measure RSRQ. Subsequently, PeNB performs the following processing.

  (1) The PeNB calculates as follows based on the RSRP and RSRQ from the terminal.

  Calculate the signal-to-noise ratio (SINR) when the terminal is scheduled by the MeNB and map it to the throughput T_m, and calculate the SINR when the terminal is scheduled on the subframe of the corresponding position of the ABS by the PeNB Then, SINR is mapped to the throughput T_p1, and the SINR when the terminal is scheduled on the subframe of the non-ABS corresponding position by the PeNB is calculated, and is mapped to the throughput T_p2.

  (2) Based on estimating the performance when the terminal belongs to a different base station, the PeNB further determines whether the terminal belongs to the Macro cell or the Pico cell, and then the cell selection shift. Adjust the value of the amount bias. The determination method may be as follows.

If T_m × (1-muting_ratio) <T_p1 × muting_ratio or T_m × (1-muting_ratio) <T_p2 × (1-muting_ratio), it is determined that the terminal belongs to the Pico cell more appropriately, and the Qoffset value is set. It may be adjusted upward (larger), otherwise T_m × (1-muting_ratio)> T_p1 × muting_ratio and T_m × (1-muting_ratio)> T_p2 × (1-muting_ratio) It may be determined that the macro cell belongs more appropriately, and the Qoffset value may be adjusted downward (smaller). Or
T_p1 × muting_ratio−T_m × (1-muting_ratio) or T_p2 × (1-muting_ratio) −T_m × (1-muting_ratio) is compared with some thresholds, and the terminal belongs to what cell appropriately And map this difference to the Qoffset value.

  Similarly, considering factors such as the load of each cell, the following is obtained.

  (3) Cell selection is performed based on the calculated specific Qoffset value of each terminal, and a cell-specific Qoffset adjustment amount is transmitted to each terminal by signaling such as paging.

  Example 5: In this example, it is assumed that the terminal is currently in a disconnected state, the terminal independently executes steps S101 to S103, and the base station of the cell that currently belongs to the terminal is a macro base station.

  Specifically, if this cell is a macro cell of a certain macro base station, the terminal may complete the following processing.

  (1) Under the measurement event configured by the upper layer, the RSRP and RSRQ of the corresponding base station in this cell and adjacent cells (including the low power base station cell Pico cell), respectively, taking measurement. Among them, for the macro base station, the RSRP and RSRQ are measured on the subframe of the non-ABS corresponding position, and for the low power base station, the RSRP and RSRQ are measured on the subframe of the ABS corresponding position.

  (2) The terminal calculates as follows based on the measured RSRP and RSRQ, respectively.

  The SINR when the terminal is scheduled by the MeNB is calculated and mapped to the throughput T_m, and the SINR when the terminal is scheduled by the PeNB is calculated and mapped to the throughput T_p.

  (3) Based on estimating the performance when the terminal belongs to a different base station, the terminal further determines whether the terminal belongs to the Macro cell or the Pico cell, and then selects the cell selection bias. Adjust the value of the transfer amount Qoffset. The determination method may be as described in Example 3.

  (4) Cell selection is performed based on the calculated specific Qoffset value of the terminal.

  Example 6: In this example, it is assumed that the terminal is currently in a disconnected state, the terminal independently executes steps S101 to S103, and the base station of the cell that currently belongs to the terminal is a low power base station. .

  Specifically, if this cell is a cell Pico cell of a low power base station, the terminal may perform the following processing.

  (1) Under the measurement event configured by the upper layer, measure the RSRP and RSRQ of the corresponding base station in this cell and adjacent cells (including the micro cell of the 某 macro base station), respectively. . Among them, for the macro base station, the RSRP and RSRQ are measured on the subframe of the corresponding position of the non-ABS, and for the low power base station, the RSRP and RSRQ are respectively measured on the subframe of the corresponding position of the ABS and the non-ABS. taking measurement.

  (2) The terminal calculates as follows based on the measured RSRP and RSRQ, respectively.

  Calculate the signal-to-noise ratio (SINR) when the terminal is scheduled by the MeNB and map it to the throughput T_m, and calculate the SINR when the terminal is scheduled on the subframe of the corresponding position of the ABS by the PeNB Then, SINR is mapped to the throughput T_p1, and the SINR when the terminal is scheduled on the subframe of the non-ABS corresponding position by the PeNB is calculated, and is mapped to the throughput T_p2.

  (3) Based on estimating the performance when the terminal belongs to a different base station, the terminal further determines whether the terminal belongs to the Macro cell or the Pico cell, and then selects the cell selection bias. Further adjust the amount of shift Qoffset. The determination method may be as described in Example 4.

  (4) Cell selection is performed based on the calculated specific Qoffset value of the terminal.

  The cell selection method in the heterogeneous network according to the embodiment of the present invention has been described in detail above. According to the embodiment of the present invention, when cell selection is performed, a parameter related to signal reception quality of a terminal is considered, for example, only signal strength (RSRP can represent signal strength) is considered. Rather, it also estimates the performance gain when the user is scheduled by different base stations by taking into account the interference received by the terminal by a parameter called reference signal reception quality (ie RSRQ), and then for each terminal Then, a dedicated cell selection deviation amount is selected, and thus the terminal can perform cell selection based on its own dedicated cell selection deviation amount. Therefore, the cell selection mechanism can be optimized, and the resource utilization rate and throughput of the system can be further improved.

  Corresponding to the cell selection method in the heterogeneous network provided by the embodiment of the present invention, the embodiment of the present invention also provides a cell selection apparatus in the heterogeneous network. Referring to FIG. 2, the apparatus includes the following units.

Signal-to-noise ratio estimation unit 201: Signals when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters related to signal reception quality of the macro base station and the low power base station measured by the terminal. Configured to estimate a noise to noise ratio;
Throughput mapping unit 202: maps the estimated signal-to-noise ratio to throughput to obtain a first throughput when scheduled by a macro base station and a second throughput when scheduled by a low power base station Composed; and
Deviation amount adjustment unit 203: Adjusts the cell selection deviation amount based on the above-described first throughput and the above-described second throughput, and sends the adjustment to the terminal based on the above-described adjusted cell selection deviation amount. , Configured to perform cell selection.

  Referring to FIG. 3, in one specific embodiment, the signal to noise ratio estimation unit 201 may include the following subunits.

  First estimation subunit 2011: using parameters related to signal reception quality of the macro base station and the low power base station measured by the terminal on all the subframes, the terminal is respectively operated by the macro base station and the low power base station. It is configured to estimate the signal-to-noise ratio when scheduled.

  Referring to FIG. 4, in another specific embodiment, the signal to noise ratio estimation unit 201 may include the following subunits.

  Second estimation subunit 2012: using parameters related to signal reception quality of the macro base station and the low power base station measured by the terminal based on the ABS configuration of the macro base station, the terminal uses the macro base station and the low power, respectively. It is configured to estimate the signal to noise ratio when scheduled by the base station.

  Among them, when an ABS is configured in a macro base station, when a terminal currently belongs to a different type of cell, a specific method for the corresponding terminal to measure RSRP and RSRQ is different.

  Specifically, when the base station of the cell that currently belongs to the terminal is a macro base station, the second estimation subunit 2012 specifically includes the signal reception quality of the macro base station measured on the non-ABS by the terminal. And the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using the parameters regarding the signal reception quality of the low power base station measured on the ABS. Configured as follows.

  Correspondingly, the deviation amount adjusting unit 203 includes the following subunits.

First computing subunit 2031: configured to multiply the first throughput by the ratio of the number of non-ABSs to the total number of subframes to obtain a first product;
A second computational subunit 2032: configured to multiply the second throughput by the ratio of the number of ABS to the number of all subframes to obtain a second product; and
First adjustment subunit 2033: configured to adjust the cell selection deviation amount based on the first product and the second product described above.

  Alternatively, referring to FIG. 5, when the base station of the cell that currently belongs to the terminal is a low power base station, the second estimation subunit 2012 is specifically configured as a macro base station measured by the terminal on a non-ABS. The first signal when the terminal is scheduled by the macro base station using the parameter related to the signal reception quality and the parameter related to the signal reception quality of the low power base station measured on the ABS and the non-ABS, respectively. Noise-to-noise ratio, second signal-to-noise ratio when the terminal is scheduled on ABS by a low power base station, and third signal pair when the terminal is scheduled on non-ABS by a low power base station It is configured to estimate the noise ratio.

  Accordingly, the throughput mapping unit 202 specifically maps the first signal to noise ratio to the first throughput, maps the second signal to noise ratio to the second throughput, and sets the third signal to noise ratio to the first throughput. Configured to map to three throughputs. Specifically, the shift amount adjustment unit 203 may include the following subunits.

Third calculation subunit 2034: configured to multiply the first throughput by the ratio of the number of non-ABSs to the total number of subframes to obtain a third product;
Fourth computational subunit 2035: configured to multiply the second throughput by the ratio of the number of ABS to the number of all subframes to obtain a fourth product;
A fifth computational subunit 2036: configured to multiply the third throughput by the ratio of the number of non-ABSs to the total number of subframes to obtain a fifth product; and
Second adjustment subunit 2037: configured to adjust the above-described cell selection shift amount based on the above-mentioned third product, fourth product, and fifth product.

  In actual applications, other factors such as cell load can be taken into account when adjusting the cell selection deviation. At this time, referring to FIG. 6, the apparatus further includes the following units.

  First throughput adjustment unit 210: configured to adjust the first throughput and the second throughput described above based on the cell load of the macro base station and the low power base station.

  Accordingly, the deviation amount adjustment unit 203 is specifically configured to adjust the cell selection deviation amount based on the adjusted first throughput and second throughput.

  Corresponding to the embodiment shown in FIG. 5, as shown in FIG. 7, the apparatus may further comprise the following units:

  Second throughput adjustment unit 220: configured to adjust the above-described first throughput, second throughput, and third throughput based on the cell load of the macro base station and the low power base station.

  Accordingly, the deviation amount adjustment unit 203 is specifically configured to adjust the cell selection deviation amount based on the adjusted first throughput, second throughput, and third throughput.

  Of course, in the embodiment of the present invention, the parameters related to the signal reception quality may include the reference signal reception power and the reference signal reception quality.

  According to the cell selection apparatus in the heterogeneous network according to the embodiment of the present invention, when performing cell selection, the parameters regarding the signal reception quality of the terminal are taken into account, for example, the signal strength (RSRP is also representative of the signal strength). As well as the interference received by the terminal due to a parameter called reference signal reception quality (ie, RSRQ) to estimate the performance gain when users are scheduled by different base stations. Then, a dedicated cell selection deviation amount is selected for each terminal, and thus the terminal can perform cell selection based on its own dedicated cell selection deviation amount. Therefore, the cell selection mechanism can be optimized, and the resource utilization rate and throughput of the system can be further improved.

  In practical applications, the adjustment process for the cell selection deviation amount may be completed independently by the terminal, so the embodiments of the present invention also provide a terminal. Referring to FIG. 8, the terminal includes the following.

Measurement unit 801: configured to measure the reference signal reception power and reference signal reception quality of a macro base station in a heterogeneous network, and the reference signal reception power and reference signal reception quality of a low power base station in a heterogeneous network And; and
Cell selection device 802 in the heterogeneous network described in the embodiment of the device described above: For example, the cell selection device in the heterogeneous network shown in FIGS.

  Alternatively, when the terminal is in the connected state, the adjustment process for the cell selection deviation amount may be completed independently by the base station, so that the embodiment of the present invention can be applied to a base station in a heterogeneous network. Also provide. The base station includes a cell selection device in a heterogeneous network as described in the device embodiment above.

  In addition, the embodiment of the above-described apparatus, terminal, and base station, and other parts not described for each of the above-mentioned units can refer to the introduction of the embodiment of the method. For example, FIG. Thru Example 6 and the like can be referred to, and a detailed description thereof will be omitted here.

  In addition, it should be explained that the above-described series of processes and apparatuses can be realized by software and / or firmware. When realized by software and / or firmware, a program constituting the software is installed from a recording medium or a network into a computer having a dedicated hardware structure, for example, a general-purpose personal computer 900 shown in FIG. Various functions can be executed when various programs are installed.

  In FIG. 9, the central processing unit (CPU) 901 performs various processes based on a program stored in the ROM 902 or a program loaded from the storage unit 908 to the RAM 903. The RAM 903 also stores data necessary when the CPU 901 executes various processes as necessary.

  The CPU 901, ROM 902, and RAM 903 are connected to each other by a bus 904. An input / output interface 905 is also connected to the bus 904.

  Also connected to the input / output interface 905 are an input unit 906 (including a keyboard and a mouse), an output unit 907 (for example, a display such as a CRT and LCD, a speaker, etc.), and a storage unit. 908 (including a hard disk) and a communication unit 909 (including a network access card such as a LAN card or a modem). The communication unit 909 performs communication processing via a network, for example, the Internet.

  If desired, drive 910 can also be connected to input / output interface 905. A removable medium 911, for example, a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor storage device, etc., may be attached to the drive 910 as necessary, and the computer program read out from the medium may be It can be installed in the storage unit 908.

  When the above-described series of processing is realized by software, a program constituting the software may be installed from a network, for example, the Internet, or a storage medium, for example, a removable medium 911.

  It should be understood by those skilled in the art that such a storage medium has a program stored therein and is a removable medium as shown in FIG. 9 that is distributed independently of the apparatus so as to provide the program to the user. It is not limited to 911. Examples of the removable medium 911 include a magnetic disk (including a floppy (registered trademark) disk), an optical disk (including a CD-ROM and a DVD), a magneto-optical disk (including MD (registered trademark)), and the like. And a semiconductor memory. Alternatively, the storage medium may be a ROM 902, a hard disk included in the storage unit 1108, etc., in which a program is stored and distributed to a user together with a device including them.

  Further, the steps of executing the above-described series of processes may be executed according to the time order in the order described above, but are not necessarily executed according to the time order. Some steps may be performed in parallel or independently of each other.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and all modifications to the present invention belong to the technical scope of the present invention unless departing from the spirit of the present invention. It should be noted that words such as “including”, “having” and the like in the embodiments of the present invention are used to encompass non-exclusive “including” and thereby include a series of elements. A process, method, article or apparatus may include not only these elements, but also other elements not explicitly specified, or include unique elements possessed by the process, method, article or apparatus. In the absence of more limitations, an element defined by the phrase “including” does not exclude other identical elements present in the process, method, article, or apparatus containing the element.

Claims (20)

A cell selection method in a heterogeneous network, comprising:
Estimate the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using the parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal. ;
Mapping the estimated signal-to-noise ratio to throughput to obtain a first throughput when scheduled by the macro base station and a second throughput when scheduled by the low power base station; and A method comprising adjusting a cell selection deviation amount based on the first throughput and the second throughput, and the terminal performing cell selection based on the adjusted cell selection deviation amount. The method of claim 1, comprising
Estimate the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, based on the signal reception quality parameters of the macro base station and the low power base station measured by the terminal. To do
Using the parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal on all subframes, the terminal performs scheduling by the macro base station and the low power base station, respectively. Estimating the signal-to-noise ratio when done. The method of claim 1, comprising
An all-most blank subframe is configured in the macro base station, and each of the terminals receives the macro base station based on parameters related to signal reception quality of the macro base station and the low power base station measured by the terminal. And estimating the signal to noise ratio when scheduled by the low power base station,
Using the parameters related to the signal reception quality of the macro base station and the low power base station, measured by the terminal based on the configuration of the all-most blank subframe of the macro base station, the terminals respectively Estimating the signal to noise ratio when scheduled by the macro base station and the low power base station. The method of claim 3, wherein
The macro base station and the low power measured by the terminal based on the configuration of the all-most blank subframe of the macro base station when a base station of a cell currently belonging to the terminal is a macro base station. Estimating the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters of the signal reception quality of the base station,
The signal regarding the signal reception quality of the macro base station measured on the non-almost blank subframe by the terminal, and the signal of the low power base station measured on the all-most blank subframe. Estimating the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters relating to reception quality;
Based on the first throughput and the second throughput, adjusting the cell selection deviation amount,
Multiplying the first throughput by the ratio of the number of non-almost blank subframes to the total number of subframes to obtain a first product;
Multiply the second throughput by the ratio of the number of all-most blank subframes to the total number of subframes to obtain a second product; and the first product and the second product Adjusting the amount of cell selection deviation based on: The method of claim 3, wherein
The macro base station and the low power measured by the terminal based on the configuration of the all-most blank subframe of the macro base station when a base station of a cell currently belonging to the terminal is a low power base station. Estimating the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters of the signal reception quality of the base station,
The parameters regarding the signal reception quality of the macro base station measured on the non-almost blank subframe by the terminal, and on the all-most blank subframe and the non-almost blank subframe, respectively. A first signal-to-noise ratio when the terminal is scheduled by the macro base station, using the measured parameter of the low power base station regarding the signal reception quality, and the terminal A second signal-to-noise ratio when scheduled on a most blank blank subframe and a third signal when the terminal is scheduled on the non-all-most blank subframe by the low power base station Estimating the noise to noise ratio,
Mapping the estimated signal-to-noise ratio to the throughput comprises
Mapping the first signal to noise ratio to a first throughput, mapping the second signal to noise ratio to a second throughput, and mapping the third signal to noise ratio to a third throughput;
Based on the first throughput and the second throughput, adjusting the cell selection deviation amount,
Multiplying the first throughput by the ratio of the number of non-almost blank subframes to the total number of subframes to obtain a third product;
Multiply the second throughput by the ratio of the number of all-most blank subframes to the total number of subframes to obtain a fourth product;
Multiplying the third throughput by the ratio of the number of non-almost blank subframes to the total number of subframes to obtain a fifth product; and the third product, the fourth power Adjusting the cell selection deviation based on a product and the fifth product. A method according to any one of claims 1-4,
Further comprising adjusting the first throughput and the second throughput based on cell loads of the macro base station and the low power base station;
Based on the first throughput and the second throughput, adjusting the cell selection deviation amount,
Adjusting the cell selection shift amount based on the adjusted first throughput and the second throughput. A method according to claim 5, comprising
Further comprising adjusting the first throughput, the second throughput, and the third throughput based on cell loads of the macro base station and the low power base station;
Based on the first throughput and the second throughput, adjusting the cell selection deviation amount,
Adjusting the cell selection shift amount based on the adjusted first throughput, the second throughput, and the third throughput. A method according to any one of claims 1 to 5, comprising
The method relating to the signal reception quality includes a reference signal reception power and a reference signal reception quality. A cell selection device in a heterogeneous network,
Estimate the signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using the parameters regarding the signal reception quality of the macro base station and the low power base station measured by the terminal A signal to noise ratio estimation unit for:
Throughput mapping for mapping the estimated signal-to-noise ratio to throughput and obtaining a first throughput when scheduled by the macro base station and a second throughput when scheduled by the low power base station A unit for adjusting a cell selection deviation amount based on the first throughput and the second throughput, and causing the terminal to perform cell selection based on the adjusted cell selection deviation amount. A device including a dosage adjustment unit. The apparatus according to claim 9, wherein
The signal to noise ratio estimation unit comprises:
The terminal is scheduled by the macro base station and the low power base station, respectively, using parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal on all subframes. Comprising a first estimation subunit for estimating said signal to noise ratio. The apparatus according to claim 9, wherein
An all-most blank subframe is configured in the macro base station, and the signal-to-noise ratio estimation unit includes:
Using the parameters related to the signal reception quality of the macro base station and the low power base station measured by the terminal based on the arrangement of the all-most blank subframe of the macro base station, the terminal An apparatus comprising a second estimation subunit for estimating the signal to noise ratio when scheduled by a macro base station and the low power base station. The apparatus according to claim 11, wherein
When the base station of the cell currently belonging to the terminal is a macro base station, the second estimation subunit is specifically:
The signal regarding the signal reception quality of the macro base station measured on the non-almost blank subframe by the terminal, and the signal of the low power base station measured on the all-most blank subframe. Configured to estimate a signal-to-noise ratio when the terminal is scheduled by the macro base station and the low power base station, respectively, using parameters relating to reception quality;
The deviation adjusting unit is
A second computational subunit for obtaining a first product by multiplying the first throughput by the ratio of the number of non-almost blank subframes to the number of all subframes;
A second computational subunit for obtaining a second product by multiplying the second throughput by the ratio of the number of all-most blank subframes to the number of all subframes; and the first product And a first adjustment subunit for adjusting the cell selection deviation amount based on the second product. The apparatus according to claim 11, wherein
When the base station of the cell currently belonging to the terminal is a low power base station, the second estimation subunit is specifically:
Parameters related to the signal reception quality of the macro base station measured on the non-almost blank subframe by the terminal and measured on the all-most blank subframe and the non-almost blank subframe, respectively. A first signal-to-noise ratio when the terminal is scheduled by the macro base station, using the parameter regarding the signal reception quality of the low power base station, and the terminal A second signal-to-noise ratio when scheduled on a blank subframe and a third signal pair when the terminal is scheduled on the non-almost blank subframe by the low power base station Configured to estimate the noise ratio,
The throughput mapping unit specifically includes:
Mapping the first signal to noise ratio to a first throughput, mapping the second signal to noise ratio to a second throughput, and mapping the third signal to noise ratio to a third throughput;
The deviation adjusting unit is
A third computational subunit for obtaining a third product by multiplying the first throughput by the ratio of the number of non-almost blank subframes to the total number of subframes;
A fourth computational subunit for obtaining a fourth product by multiplying the second throughput by the ratio of the number of all-most blank subframes to the number of all subframes;
A fifth computational subunit for obtaining a fifth product by multiplying the third throughput by the ratio of the number of non-almost blank subframes to the number of all subframes; and the third power An apparatus comprising: a second adjustment subunit for adjusting the cell selection shift amount based on a product, the fourth product, and the fifth product. The device according to any one of claims 9 to 12,
A first throughput adjustment unit for adjusting the first throughput and the second throughput based on cell loads of the macro base station and the low power base station;
Specifically, the deviation amount adjusting unit includes:
An apparatus configured to adjust the cell selection shift amount based on the adjusted first throughput and second throughput. An apparatus according to claim 13,
A second throughput adjustment unit for adjusting the first throughput, the second throughput, and the third throughput based on cell loads of the macro base station and the low power base station;
Specifically, the deviation amount adjusting unit includes:
An apparatus configured to adjust the cell selection shift amount based on the adjusted first throughput, the second throughput, and the third throughput. The device according to any one of claims 9 to 13,
The parameter related to the signal reception quality includes a reference signal reception power and a reference signal reception quality. A terminal,
A measurement unit for measuring a parameter related to signal reception quality of a macro base station and a low power base station; and a cell selection device in a heterogeneous network according to any one of claims 9 to 16, Terminal. A base station in a telogian network,
A base station comprising the cell selection device in the heterogeneous network according to any one of claims 9 to 16. A program product storing machine-readable instruction codes,
A program product that, when read and executed by a machine, causes the cell selection method in the heterogeneous network according to any one of claims 1 to 8 to be executed. A recording medium carrying a machine-readable command code,
9. A recording medium that causes the cell selection method in the heterogeneous network according to any one of claims 1 to 8 to be executed when the command code is read and executed by a machine.

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